<template>
  <aside class="sidebar">
    <div class="sidebar-header">
      <h2>AI问答系统</h2>
      <button class="new-chat-btn" @click="handleNewChat">
        <span>+ 新对话</span>
      </button>
    </div>

    <div class="conversation-list">
      <div v-if="conversations.length === 0" class="empty-tip">
        <div class="empty-content">
          <span>暂无对话</span>
        </div>
      </div>
      <template v-else>
        <div
          v-for="conversation in conversations"
          :key="conversation.id"
          class="conversation-item"
          :class="{ active: activeId === conversation.id }"
          @click="selectConversation(conversation.id)"
        >
          <span>{{ conversation.name || "新对话" }}</span>
        </div>
      </template>
    </div>
  </aside>
</template>

<script>
import { ref } from "vue";
import { useRouter } from "vue-router";

export default {
  props: {
    conversations: {
      type: Array,
      required: true,
      validator: (value) => {
        return Array.isArray(value);
      },
      default: () => [],
    },
  },
  emits: ["select", "new-chat"],
  setup(props, { emit }) {
    const router = useRouter();
    const activeId = ref(null);

    const selectConversation = (id) => {
      activeId.value = id;
      emit("select", id);
    };

    const handleNewChat = () => {
      activeId.value = null;
      emit("new-chat");
      router.push({ name: "AiHomeView" });
    };

    return {
      activeId,
      selectConversation,
      handleNewChat,
    };
  },
};
</script>

<style scoped>
.sidebar {
  width: 280px;
  height: calc(100vh - 70px);
  background-color: #fff;
  border-right: 1px solid #eef0f3;
  display: flex;
  flex-direction: column;
}

.sidebar-header {
  padding: 1rem;
  border-bottom: 1px solid #eef0f3;
  background-color: #fafafa;
  position: sticky;
  top: 0;
  z-index: 1;
}

.sidebar-header h2 {
  margin: 0 0 1rem 0;
  font-size: 1.2rem;
  color: #333;
  font-weight: 600;
}

.new-chat-btn {
  width: 100%;
  padding: 0.5rem;
  background-color: #1890ff;
  color: white;
  border: none;
  border-radius: 4px;
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  transition: background-color 0.3s;
}

.new-chat-btn:hover {
  background-color: #40a9ff;
}

.conversation-list {
  flex: 1;
  overflow-y: auto;
  padding: 0.5rem;
  display: flex;
  flex-direction: column;
}

.empty-tip {
  flex: 1;
  display: flex;
  align-items: center;
  justify-content: center;
}

.empty-content {
  padding: 0.75rem;
  color: #999;
  font-size: 0.9rem;
  text-align: center;
}

.conversation-item {
  padding: 0.75rem;
  border-radius: 4px;
  cursor: pointer;
  margin-bottom: 0.25rem;
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
  transition: background-color 0.3s;
}

.conversation-item:hover {
  background-color: #f5f7fa;
}

.conversation-item.active {
  background-color: #e6f4ff;
  color: #1677ff;
  font-weight: 600;
}
</style>
